Self-Distracting Cage

• US 20080288073A1
• Filed: 05/17/2007
• Published: 11/20/2008
• Est. Priority Date: 05/17/2007
• Status: Active Grant

• Current Assignee: Depuy Synthes Products Incorporated (Johnson & Johnson)
• Original Assignee: Depuy Spine Incorporated (Johnson & Johnson)
• Inventors: Renganath, Naren, Fisher, Michael Alan, Presbrey, Glen, Connolly, Steven
• Granted Patent: US 8,273,124 B2
• Time in Patent Office: Days
• US Class Current: 623/17.12
• CPC Class Codes: A61F 2/30742 Bellows or hose-like seals; Sealing membranes A61B17/8808 takes precedence; sealing membranes for retaining bone substitute A61F2/2846
• CPC Class Codes: A61F 2/441 made of inflatable pockets or chambers filled with fluid, e.g. with hydrogel
• CPC Class Codes: A61F 2/4425 made of articulated components
• CPC Class Codes: A61F 2/4455 for the fusion of spinal bodies, e.g. intervertebral fusion of adjacent spinal bodies, e.g. fusion cages intervertebral discs A61F2/442
• CPC Class Codes: A61F 2/4465 having a circular or kidney shaped cross-section substantially perpendicular to the axis of the spine
• CPC Class Codes: A61F 2/4611 of spinal prostheses
• CPC Class Codes: A61F 2/484 Fluid means, i.e. hydraulic or pneumatic
• CPC Class Codes: A61F 2002/30433 using additional screws, bolts, dowels, rivets or washers e.g. connecting screws
• CPC Class Codes: A61F 2002/30538 for adjusting angular orientation
• CPC Class Codes: A61F 2002/3055 for adjusting length
• CPC Class Codes: A61F 2002/30583 filled with hardenable fluid, e.g. curable in-situ
• CPC Class Codes: A61F 2002/30586 having two or more inflatable pockets or chambers
• CPC Class Codes: A61F 2002/30601 telescopic
• CPC Class Codes: A61F 2002/443 having two transversal endplates and at least one intermediate component
• CPC Class Codes: A61F 2002/4693 hydraulic
• CPC Class Codes: A61F 2210/0085 hardenable in situ, e.g. epoxy resins
• CPC Class Codes: A61F 2220/0041 using additional screws, bolts, dowels or rivets, e.g. connecting screws
• CPC Class Codes: A61F 2250/0006 for adjusting angular orientation

Abstract

Various spinal implants and methods for stabilizing the spine are provided. In one exemplary embodiment, a spinal implant is provided having an expandable container with an interior volume that is selectively expandable between a compressed condition and an expanded condition. The expandable container is coupled to a superior endplate member having a bone-contacting surface and an engagement surface effective to mate with a superior surface of the expandable container, and an inferior endplate member having a bone-contacting surface and an engagement surface effective to mate with an inferior surface of the expandable container. In addition, at least one inlet port is formed in the expandable container and is effective to communicate a fluid to at least one cavity disposed within the interior volume of the expandable container.

Claims

1. A spinal implant, comprising:

an expandable container having an interior volume that is selectively expandable between a compressed condition and an expanded condition;

a superior endplate member having a bone-contacting surface and an engagement surface effective to mate with a superior surface of the expandable container;

an inferior endplate member having a bone-contacting surface and an engagement surface effective to mate with an inferior surface of the expandable container; and

at least one inlet port formed in the expandable container that is effective to communicate a fluid to at least one cavity disposed within the interior volume of the expandable container.

2. The implant of claim 1, further comprising an angular adjustment mechanism configured to enable continuously variable angular adjustment of the superior and inferior endplate members with respect to a plane extending horizontally therethrough.

3. The implant of claim 2, wherein the angular adjustment mechanism comprises at least one articulating pleated member extending between the superior and inferior endplate members.

4. The implant of claim 2, wherein the angular adjustment mechanism comprises an articulating joint disposed within at least one of the superior and inferior endplate members.

5. The implant of claim 4, wherein the articulating joint is a ball joint.

6. The implant of claim 1, wherein the expandable container contains a continuously variable height adjustment mechanism.

7. The implant of claim 6, wherein the height adjustment mechanism comprises at least one hydraulic mover.

8. The implant of claim 7, wherein the at least one hydraulic mover is a curable material.

9. The implant of claim 7, wherein the at least one hydraulic mover is an expandable balloon.

10. The implant of claim 7, wherein the at least one hydraulic mover is a piston.

11. The implant of claim 1, wherein the expandable container and the superior and inferior endplate members have a combined minimum height of about 5 mm in the compressed condition and a combined maximum height of about 15 mm in the expanded condition.

12. The implant of claim 1, wherein the superior and inferior endplate members are rigid.

13. The implant of claim 1, wherein the superior and inferior endplate members include a formable component.

14. The implant of claim 13, wherein the elastomeric component is chosen from the group consisting of polyurethanes, silicones, high-durometer hydrogels, calcium phosphate cements, polymethylmethacylates, tetraethyleneglycol dimethacrylates, their blends and derivatives.

15. A method for distracting two adjacent vertebra, comprising:

surgically delivering a selectively expandable spinal fusion implant into an intervertebral disc space;

expanding the spinal implant until a superior endplate and an inferior endplate of the spinal implant contact opposing bony surfaces of the two adjacent vertebra; and

adjusting the expansion of the implant until the two adjacent vertebra are at a desired separation.

16. The method of claim 15, wherein the surgically delivering step is conducted in a minimally invasive surgical procedure.

17. The method of claim 16, wherein the spinal fusion implant is delivered through one of an access port and a cannula.

18. The method of claim 15, wherein the surgically delivering step is conducted while the implant is at a compressed height of about 5 mm.

19. The method of claim 15, wherein expanding the implant includes selectively expanding the implant to any height appropriate for the intervertebral disc space.

20. The method of claim 15, further comprising making angular adjustments to at least one of the superior and inferior endplates with respect to a plane extending horizontally therethrough.